A Series of Fortunate Events: Glacier Point, Living Up to the Hype

Glacier Point on the rim of Yosemite Valley is hands-down one of the most spectacular places one can stand in the world. There's just no place like it. And it's noisy. It's crowded. There is a busy and often full parking lot. And despite that, it is worth putting up with, because there just aren't that many places where you can look straight down for 3,000 feet, and at the same time see the iconic rocks of the upper valley from a unique angle.

It takes a little effort to get there. One has to drive about 25 miles from the floor of Yosemite Valley up a narrow winding road. One has to wade through the crowds to get the edge of the precipice. But no matter how many times I've stood there, I can never fail to be in awe that such places exist. In one sweeping view one can see the north valley wall from the vicinity of the Three Brothers and Yosemite Falls, past Yosemite Point, on to North Dome and Basket Dome, across the deep trough of Tenaya Canyon to Half Dome. And below your feet there is the floor of Yosemite Valley, the meadows, the forests, the parking areas, the resorts, all from a nearly vertical perch at 3,200 feet (980 m).

It's from a high point like this one that I can best appreciate the work of the glaciers that altered a narrow river-carved canyon into the wide, flat floor we see today. The earliest glaciers filled the valley to the rim (the Pre-Tahoe stage around 800,000 years ago), while the later advances only filled the valley to one-third or so of the total depth (the Tahoe stage at 130,000-65,000 years, and the Tioga stage from 20,000 to 13,000 years ago). The domes, like North Dome, Basket Dome and Half Dome, rose above the ice at all times. Their rounded shapes are the result of exfoliation, the tendency of slabs to break off the edges and corners of solid monoliths of granitic rock as erosion took weight off the surface of the rock. Glaciers helped excavate the rock from the jointed face of Half Dome, but never overtopped the gigantic rock.

One might think that a view like this is unchanging on a human time scale, but that's not exactly true. It's a little tricky to see it in the shadows, but look at the whitish exposure of granite to the left of Half Dome in the picture above. That scar didn't exist prior to 2009. Every visitor prior to March of that year saw something different. The Ahwiyah slide involved thousands of tons of rock that fell 1,800 feet to the floor of Tenaya Canyon. The resulting explosion of rock destroyed hundreds of trees on the valley floor. To see some before and after pictures, click here for a look.

Our class finished at Glacier Point and headed back the vehicles, but we weren't done with standing in dramatic places. That will be in the next post!

Reflections on Yosemite and Mass Wasting

OK, not philosophical reflections, but literal reflections. One of my favorite spots to visit on the floor of Yosemite Valley is the Mirror Lake area, due to the relative peace and serenity brought about by the lack of cars and other urban distractions. Just people walking about quietly. Mirror Lake is not exactly a lake, and not exactly a river, and for a good part of the year it is entirely dry.

Tenaya Creek is a relatively minor tributary of the Merced River, but Tenaya Canyon is nearly as deep as the Grand Canyon. That would seem to be a bit of a mystery, since the size of glaciers in a canyon can be roughly comparable to the size of the watershed, and it looks like there was a very large glacier here. Studies of the glacial topography help to explain the disparity: large masses of glacier ice spilled over the divides from the Tuolumne River drainage, adding to the ice load in Tenaya Canyon. As big as they were, glaciers never overrode the summit of Half Dome, which looms thousands of feet above the lake. They instead undercut part of the base of the dome, taking advantage of joint patterns in the granitic rock to quarry rock away from the 700 foot-high face.Mirror Lake developed several thousand years ago when a large rockfall collapsed off the north wall of the canyon, damming up Tenaya Creek. The lake mostly filled with sand and was turning into a meadow, but heavy riverflows during spring runoff scoured out the river channel and left some very wide pools that are excellent for photographing (and just appreciating) the cliffs and domes that are reflected from above.

Lest one thinks that the rockfalls in Yosemite are a thing of the past, a large rockfall occurred here just a few years ago (see some posts on the Ahwiyah Point fall here and here). Ahwiyah Point is the prominent summit just east of Half Dome (below). The rockfall destroyed hundreds of trees, and a hiking trail, which is still closed to entry due to continuing danger from falling rocks.

Mirror Lake is not hard to get to (a tram stops just about a mile away), and one can even ride a bicycle most of the way up. There is a small network of trails around the pools, and the main trail climbs out of Yosemite at Snow Creek. It is a very beautiful corner of a very beautiful valley. Don't miss it if you get a chance to visit!

Random Thoughts on Yosemite in Spring

My last couple of posts on Yosemite in springtime followed a theme of some sort, rockfalls or waterfalls and such, but I also just plain saw a lot of beauty derived from the bounty of water at this time of year. The nice thing about a place like Yosemite (and any other kind of park) is the richness of color and texture in features big and small. The picture above is of some redbuds that are still blooming, along with a groundcover teeming with flowers of all kinds.

It was raining prior to our arrival...moisture was everywhere, including the droplets on the clover by the highway where we looked at Grouse Creek Falls. The clouds were moving eastward ahead of us, giving an interesting perspective to the little noticed cliffs around Stanford Point (little-noticed because everyone is looking east to El Capitan, Half Dome, and Bridalveil Fall from the Tunnel View parking lot. It's one of those cases where these cliffs would be world-famous if they were located anywhere else.

Half Dome was putting on a show today, too. This view from the Curry Village parking lot is hard to miss, although I almost always get a telephone wire in the picture. Whose idea was it to string a telephone wire across the view of one of the most iconic rocks in the American West?

Tenaya Creek was running full, and will deserve an entire post of its own in a day or two. The water is strikingly clear, primarily because the watershed above has been stripped almost entirely clean of soil by the glaciers that coursed through the canyon as recently as 13,000 years ago. The water flows over barren rock over much of its course and thus carries relatively little sediment.

One more waterfall to add to the mix. This is Royal Arch Cascade, which tumbles down the canyon wall just west of the Arch. Most people don't see this particular view, as it is a zoom view of just the very top of the waterfall.

It is easily viewed from the parking lot of the Ahwahnee Hotel. We had an appetizer in the bar for the price of a dinner! And it felt worth it...

As we left the valley, we made a brief stop at Valley View, another one of the iconic views of Yosemite just west of the "Gateway", the towering cliffs of El Capitan and Cathedral Rocks. Jet contrails usually screw up pictures of nature, but there seems to be a kind of symmetry to the ones seen here.